BikeRadar Builds | Tom’s Santa Cruz Chameleon mullet singlespeed

Tom's do-it-all hardtail has been pared down to just the essentials

Tom Marvin’s Santa Cruz Chameleon mullet singlespeed

Welcome to BikeRadar Builds – a new occasional series in which the BikeRadar team get to show off their personal bikes and builds, along with their back gardens (or, in my case, the local park because my garden is far too scraggly to put out there in public)!

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This week we’re going to take an in-depth look at my Santa Cruz Chameleon – a previous BikeRadar long-term bike – that’s served me well over the past year, but has now morphed into something quite different to what I first swung a leg over.

As the name suggests, the Chameleon is a versatile bike. Santa Cruz says it’s suitable for pretty much anything from hardcore trail rides to bikepacking adventures in the middle of nowhere.

The Chameleon is available in both alloy and carbon versions, and its this latter version that I’ve been riding.

The bike arrived as a 27.5+ build with Santa Cruz’s Reserve carbon wheels, a SRAM GX Eagle drivetrain and Guide brakes, and a Performance level 34 fork from Fox with 130mm of travel.

However, as you can see that’s nearly all gone. 

Introducing BikeRadar Builds

BikeRadar Builds is our occasional look at the team’s personal bikes, including custom rigs, commuters, dream builds and more.

This is our chance to geek out about the bikes we love riding day-to-day, and explore the thinking (or lack of it!) behind our equipment choices.

At university, I was obsessed with singlespeed bikes, slowly grinding my knees’ cartilage to a fine paste gurning up Scottish mountains for no other reason than I enjoyed the challenge.

So, with that option available to me again, I chucked the gears in the (parts) bin and single-speeded the Chameleon.

Santa Cruz Chameleon mullet singlespeed
Swinging dropouts alter chainstay lengths to tension the chain.
Tom Marvin / Immediate Media

The carbon SRAM X1 carbon crankset (175mm) remains on the bike with its 30t chainring. Singlespeed sprocket conversions are relatively easy to find for a ‘regular’ Shimano freehub, but less so for the XD driver that came on the Hope Pro4 hub on this build.

However, Gussett offers an XD 1-ER kit, which has an XD lockring system, to which you can bolt a singlespeed sprocket. 

Santa Cruz Chameleon mullet singlespeed
Singlespeed converters for XD drivers aren’t the most common items, but Gusset makes one.
Tom Marvin / Immediate Media

This has allowed me to keep the standard dropout and Hope hub, with its Boost spacing.

Santa Cruz offers a singlespeed dropout (without the mech hanger), but this drops the rear hub spacing to 142mm – a more common size for dedicated singlespeed hubs without a regular freehub. (Singlespeeders haven’t entered the modern world, yet, and the lack of a regular freehub body means spoke triangulation can still be improved on the narrower hub).

I was running the bike with a 16t sprocket, but have since dropped it to 17t, giving me a 30:17 ratio which is fairly spinny for longer climbs.

It’s a touch lower than I used to run at uni, but the aforementioned knees might not thank me for pummelling them quite so much these days.

Tension is controlled by neat looking (but not completely infallible) swinging dropouts, which adjust the chainstay length.

Tension is held by a hidden bolt in each dropout, though I’ve not found it the most secure system, and have had to re-tension the system on the trail a few times.

What I find odd is that, with the stock chainring Santa Cruz supplies and despite the bike being labelled as ready for singlespeeds, the chain has zero clearance with the bottom of the chainstay protector.

Now, for clarity, it has never caused an issue, it’s not rubbing on any carbon (and has enough clearance without the protector for that not to happen) and my chain hasn’t worn out thanks to it (just the chainstay protector), but it is a bit odd.

Santa Cruz Chameleon mullet singlespeed
I’m not sure why clearance down here for the chain is so slim.
Tom Marvin / Immediate Media

On the back I’ve kept the Santa Cruz RSV wheel, with its 37mm-wide Reserve carbon rim, and onto this I’ve mounted a 2.6in Bontrager SE4 tyre.

Arguably the rim is a touch wide for a 2.6in tyre, but I’ve not found it to be a problem. It blows up huge, offering decent protection for the rim and a smidge of comfort. I’m running it at 17psi (I weigh 75kg).

Why the SE4? Well, it’s super grippy in a range of conditions, but still doesn’t seem to roll too slowly – ideal when you need all the help you can get up hills.

Oh, and this was a pre-release version with ‘prototype’ written on the sidewall, and who wouldn’t want that on their bike?

Santa Cruz Chameleon mullet singlespeed
Who wouldn’t want ‘prototype’ somewhere on their bike?!
Tom Marvin / Immediate Media

The bike originally came with a pair of Maxxis Rekon 27.5in x 2.8in tyres, but they didn’t offer me the support in the corners I really wanted, with the front tyre squirming a little more than I like when it was pushed hard.

As such, I’d quickly swapped it to a 29in front wheel with a 2.6in tyre. This setup feels much more predictable, while still offering loads of grip and roll-over smoothness – and has remained because I like the feel of the bigger wheel up front. It’s a fairly basic Roval alloy wheel, certainly not as posh as the rear, but it does its job.

One thing I have found is that the rim is really loose, so getting tubeless tyres to pop into the rim and inflate is a pain. It needs much more tape in the rim bed, I reckon.

I’ve kept the Bontrager theme going with a 29× 2.6in SE5 front tyre. It’s one I’ve liked for a few years, and again, it mixes grip with stability and reasonable rolling resistance, pumped up to 18psi. Sadly, there’s no ‘prototype’ embossed on the sidewall of this one.

The other major component is the fork. It’s a Marzocchi Z2, which replaced (for testing purposes, rather than anything else) the Fox Performance 34 that was on there.

They’re very similar forks, with Marzocchi being owned by Fox and the 34/Z2 sharing much of the same platform. The Z2 has a slightly more basic Rail damper than the GRIP unit in the 34, but generally speaking, it’s performing well.

I like my forks relatively fast, so I’m running 89psi with two clicks of rebound damping and two volume spacers.

Marzocchi Bomber Z2
I had Marzocchi Bomber Z2s on my first ‘proper’ mountain bike!
Tom Marvin / Immediate Media

For reasons no more significant than they were in the garage, I’m running a pair of SRAM Code brakes.

They are fairly ‘special’ given they have the red calipers and carbon levers – not a stock RSC option. Do I need DH/enduro level brakes on a trail hardtail? No. Do I care? No. 

The levers are adjusted to bite just over a finger’s depth from the grips, and I set my levers relatively flat. I’m running them with 180mm rotors front and back to prevent my eyes popping out every time I stop.

The cockpit is also personalised, with a 35mm RaceFace Atlas stem and 800mm alloy Joystick 8bit bars with 20mm of rise.

They’re furnished with my favourite Santa Cruz Palmdale grips. These are great value for money, wear well, are comfy to haul on and only have one inner collar, so you can get the full use of the bars’ 800mm width.

Santa Cruz Chameleon
I’m more than happy with alloy bars on my bikes.
Tom Marvin / Immediate Media

Finally, I’ve fitted a 150mm RockShox Reverb dropper, with the original WTB saddle perched on top, and there’s a pair of Nukeproof Horizon CS pedals – a favourite thanks to their pinned cage that gives great feel through normal trail shoes.

All said and done?

So, what’s the bike like to ride then? Well, in truth, a whole heap of fun.

Virtually every bike is compromised in some way, but few are compromised in so many ways, but that makes this bike a staple of my stable.

The gearing is a pain to get across town with, but on the majority of climbs actually works pretty well. You’re forced to push harder and consequentially I’ve found it faster in a lot of places – you simply can’t shift down and spin. It’s a lot more tiring, so I certainly get a good workout on the Chameleon.

When it comes to descending, the large volume rear tyre adds some ‘give’ to the bike, but it’s most definitely a hardtail, with an emphasis on the ‘hard’.

The bike bumps and clanks along, robbing speed here and there, and pummelling me to pieces on all but the smoothest of tracks. Getting it to maintain speed is hard and you have to think about every move you make.

With my legs spinning out at the merest hint of a negative incline, I’m forced to pick lines that will help keep me rolling, and brake late and little so I don’t lose too much hard-earned speed. It is, in the truest sense, involving.

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Combine climbs and descents together and the mix is intoxicating – it’s physically hard, mentally draining, uncomfortable and almost always the wrong tool for the job. And because of that, it’s utterly brilliant.

Santa Cruz Chameleon C mullet singlespeed custom spec

  • Frameset: Santa Cruz Chameleon C, Large
  • Fork: Marzocchi Z2, 130mm
  • Groupset: SRAM X1 carbon crank, Gusset XD 1-ER, 30:17
  • Brakes: SRAM Code RSC (custom), 180mm/180mm
  • Wheels: Santa Cruz Reserve 37 27.5in on Hope Pro4 rear, Roval Traversee alloy 29in front
  • Tyres: Bontrager SE4 Team Issue Prototype 27.5×2.6 rear, Bontrager SE5 Team Issue 29×2.6 front
  • Cockpit: RaceFace Atlas 40mm stem, Joystick 8bit 800mm bar, Santa Cruz Palmdale grips
  • Seatpost: RockShox Reverb 150mm
  • Saddle: WTB Silverado
  • Price: £1,399 (frame only)